// global objects
const a: Array<number> = [1, 2, 3]
const date = new Date()
const reg = /abc/

// build-in object
Math.pow(2, 2)

// DOM and BOM
let body = document.body
let allLis = document.querySelectorAll('li')
allLis.keys

// Utility types
interface IPerson1 {
    name: string
    age: number
}

let wind1: IPerson1 = { name: 'xszi', age: 20 }
type IPartial = Partial<IPerson1>
let wind2: IPartial = { name: 'xszi'}

// 忽略那么属性
type IOmit = Omit<IPerson1, 'name'>
let wind3: IOmit = { age: 20 }